The present invention relates to an evaporative condensing apparatus for use in an air conditioner (cooler), and more particularly to such an evaporative condensing apparatus which greatly improve the working efficiency of the air conditioner (cooler).
Air conditioners (coolers) are intensively used in most countries in summer for air-conditioning buildings, rooms, trains, cars, etc. When an air conditioner is operated, it consumes much energy due to a high pressure compressor is used in a cooling medium system. The energy saving problem may do nothing wit mid-east contries or other patroleum producing contries, but it is very serious in most area of the world lack of energy source especially in summer time while a huge amount of air conditioners are used. In a regular air conditioner, a liquid state cooling medium is guided to a medium coil of an evaporator to make a heat exchange with air, permitting cooling air to be guided into the inside space of a building, room, train or car. After this heat exchange process, the liquid state cooling medium is changed into a gas state, the gas state cooling medium is then compressed by a compressor to a certain high pressure and pumped to the medium coils of a condenser where the gas state cooling medium is returned to the liquid state again due to a temperature dropping by a cooling system. In which, the lower temperature can be reached, the lower relative critical pressure is needed and then a low pressure compressor can be employed for energy saving. FIG. 1 shows a liquid-gas curve obtained form R-22 cooling medium. As indicated the cooling medium can easily be condensed with low relative pressure when at a low temperature, for example: when at 45.degree. C. as point C of the curve, which is almost a lowest temperature the a conventional condensing unit can reach to, in which the relative critical pressure needed for condensing the medium is about 18 kg/cm.sup.2, if the temperature can be dropped to 30.degree. C. as point B, by a high efficient cooling system the relative critical pressure needed for condensing will be drastically reduced to 12.27 kg/cm.sup.2. Therefore, the energy consumption of an air conditioner is reverse proportion to the efficiency of the cooling system used in the condensing unit.
Further, the cooling systems of conventional condenser include three types, namely, the air cooling type, the water cooling type and the evaporative type. An air cooling type condenser uses convention currents of air to carry heat away from its condensing coils. In order to let heat be quickly carried away, much air contact surface and high currents of air are needed. Therefore, an air cooling type condenser is heavy, consumes much energy, and produces high noise during its operation. A water cooling type condenser uses cooling water to carry heat away from its condensing coils. However, a water cooling type condenser is expensive, and consumes much cooling water. Further, the installation of a water tower for a water cooling type condenser is complicated, and may cause an American veteran syndrome. An evaporative type air conditioner dissipates heat by means of evaporation of water which is sprayed continuously on to the surface of the medium coil. Theoretically one liter of water absorbs about 539 cal. Evaporating latent heat when evaporated. Therefore the heat dissipation effect of an evaporative type is much better than an air cooling type and a water cooling type. However, when a conventional evaporative type condenser is used, it still has two disadvantages, firstly, the spraying water can not be held on a smooth surface of a bare metal condensing coil for an enough period of time to let the water getting fully evaporated, it will flows off from the condensing coils before evaporated. Therefore the heat dissipation effect is not fully developed, it can't do much better than the other two types; secondary, a large water storage means is needed to collect waste water that is not evaporated at the evaporative condensing unit of the air conditioner.